Devonian Eustatic Events in the Western United States and Their Biostratigraphic Responses

摘要: Abstract Sixteen deepening events, of which 11 were eustatic, and six regressive episodes, 3 acted as primary controls on Devonian sedimentation biotic changes in the Western United States. Many stratigraphic unit boundaries, especially within limestone sequences, resulted from eustatic rises, widespread unconformities produced by falls. Eustatic efficacy evidently was a highly significant control bio-events caused diversity changes, macrofaunal biofacies shifts, local worldwide extinctions. An Early (pesavis Zone) regression, is here considered first intra-Devonian fall, dramatically changed brachiopod (also called faunal realms). Late falls just before close Frasnian Famennian Stages presaged extinctions conodonts macrofaunas.